The present invention relates to improvements in diagnostic techniques, and more particularly to diagnostic techniques for detecting and identifying DNA or RNA damage. The invention has particular utility in the detection of cervical cancer and will be described in connection with such utility, although other utilities are contemplated, as will be discussed below in detail, including detection of other cancers and other disease conditions, as well as health conditions brought out by exposure to environmental insults such as radiation, metals, smoke and solvents.
The current gold standard for detecting cervical cancer in women is the so-called xe2x80x9cPAP Smear.xe2x80x9d However, the reliability of PAP Smear testing, which relies upon a technician""s observations, under the microscope, of cellular morphology, may be compromised by technician fatigue and/or subjectivity. Even very experienced technicians may misread a slide. If a false-positive is xe2x80x9ccalledxe2x80x9d or the slide results in an xe2x80x9cuncertainxe2x80x9d call, the physical may err on the side of the patient""s safety, and call for a hysterectomy (uterus removal) or total hysterectomy (uterus and ovary removal). This results in the patient taking a lifetime dose of hormone replacement medications to keep the body in balance. Of course, the failure to identify xe2x80x9ca pre-cancerous conditionxe2x80x9d could lead to an even more disastrous result to a patient.
It is thus a primary object of the invention to overcome the aforesaid and other disadvantages of the prior art. Another object of the invention is to provide an analytical technique for detecting and diagnosing disease conditions, as well as health conditions due to exposure to environmental conditions, by detecting and identifying DNA or RNA damage markers. Another more object of the invention is to provide a reliable, totally objective analytical technique for detecting cancer.
In order to effect the foregoing and other objects, the present invention provides an analytical technique for detecting cancer or other disease and/or health conditions based on measurement of free levels of nucleotide excision products resulting from DNA or RNA damage, such as 8OH2xe2x80x2dG-8 hydroxy 2xe2x80x2 deoxyguanosine; O6MGxe2x80x94O-6-methylguanine; 2xe2x80x2dGxe2x80x942xe2x80x2deoxyguanosine; 7MGxe2x80x947-methylguanine; 8NGxe2x80x948-nitroguanine; 8OHGxe2x80x948-hydroxyguanine; 8OH2xe2x80x2dAxe2x80x948-hydroxy-2-deoxyadenosine; 8OHAxe2x80x948-hydroxyadenine; 5OH2xe2x80x2dCyxe2x80x945-hydroxy 2xe2x80x2deoxycytidine; 5OHUxe2x80x945-hydroxyuracil; 3NTxe2x80x943-nitrotyrosine; or 3 CITxe2x80x943-chlorotyrosine in biological samples from selected areas of the body. More particularly, the present invention is based on the hypothesis that specific areas of the body are semi-isolated in-situ biochemical environments for nucleotide excision products such as 8OH2xe2x80x2dG or other nucleotide excision products, and that the levels of such free 8OH2xe2x80x2dG or other nucleotide excision products in the semi-isolated environment magnify the combined defects of DNA or RNA damage and repair mechanisms. By way of specific example; the effective damage and repair rate increases in DNA in cancer, or pre-cancerous cells, has been found to be magnified by accumulation in the extra-cellular matrix in selected areas of the body of 8OH2xe2x80x2dG. For example, as applied to cervical cancer, the cervix has been found to be a semi-isolated in-situ biochemical environment which may be accessed through cervico vaginal lavage sampling. Thus, an objective analytical technique for determination of cervical cancer is provided.